1. Field of the Invention
The present invention relates to a sliding-type mobile terminal. More particularly, the present invention relates to a guide device for a sliding unit in a sliding-type mobile terminal.
2. Description of the Related Art
Mobile terminals include a notebook, a Personal Digital Assistant (PDA), a radiotelegraph, an MP3player, a Portable Multimedia Player (PMP), a cellular phone, a smart phone, and the like. Among them, a light and compact cellular phone or a smart phone having a communication function is easy to carry and has evolved into a mobile terminal which allows convenient viewing in numerous modes to meet the demand for video communication, games, on-demand video, and TeleVision (TV) viewing as well as simple voice communication and short text message transmission with the emergence of multimedia environments.
The mobile terminals can be classified into a bar type, a folder type, and a sliding type according to their appearance. The sliding-type mobile terminal includes a main body, a sliding body which slides on the main body, and a sliding unit which couples the main body with the sliding body.
FIG. 1 is a perspective view of a closed state of a sliding-type mobile terminal according to the related art and FIG. 2 is a perspective view of an open state of a sliding-type mobile terminal according to the related art.
Referring to FIGS. 1 and 2, a sliding-type mobile terminal 200 includes a main body 20 and a sliding body 22, which slides on the main body 20 to open or close a top surface of the main body 20. On an opening/closing region of the top surface of the main body 20 are disposed a key pad 201 having a plurality of keys and a microphone device 202. On a top surface of the sliding body 22 are provided a display unit 221, another keypad 222, and a speaker device 223. Between the top surface of the main body 20 and a bottom surface of the sliding body 22 is mounted a sliding unit for semi-automatically opening or closing the sliding body 22 in a linear manner.
FIG. 3 is a perspective view of a guide device for a sliding unit according to the related art and FIG. 4 is a cross-sectional view of a guide device for a sliding unit according to the related art.
Referring to FIGS. 3 and 4, a sliding unit employed in a sliding-type mobile terminal 200 provides a guide device 30 for allowing the sliding body 22 to move linearly on the main body 20. The guide device 30 includes a sliding body bottom surface 31 and a guide plate 32 assembled to face the bottom surface 31. A latch member 310 extends along a longitudinal direction of the sliding body 22 at both ends of the sliding body bottom surface 31, and a rack member 320 is provided at both ends of the guide plate 32 to be assembled to the latch member 310. The rack member 320, which is in a bent hook shape, has an injection portion 321 formed of PolyOxyMethylene (POM) to surround outer and inner surfaces and an end portion of the rack member 320. The injection portion 321 may be formed by insert-injection in the rack member 320. The injection portion 321 made of POM has been provided to improve sliding sensitivity during opening or closing of the sliding body 22.
However, since the latch member 320 and the injection portion 321 made of POM are formed by insert-injection in the typical guide device 30, some part may have severe friction and in particular, a sliding operation may not be uniform and smooth according to injection conditions and painting conditions. Such a state may shorten the lifespan of the sliding unit.
Therefore, a need exists for a guide device for a sliding unit in which a sliding operation of a sliding body is smooth and a lifespan of which is lengthened by minimizing generation of a scratch during opening or closing of a sliding-type mobile terminal.